Friday, 22 February 2013

2.60 describe how the immune system responds to disease using white blood cells, illustrated by phagocytes ingesting pathogens and lymphocytes releasing antibodies specific to the pathogen

White blood cells are specialised cells which can stop pathogens in your body.

Phagocytes
They can detect the presence of pathogens because of chemicals they give off.
The cell then engulfs the pathogen. It then destroys the cell with digestive enzymes.

Lymphocytes
They release anti-bodies that are specific to the pathogen.
When a lymphocyte meets its specific pathogen it divides: one cells it creates being a memory cell; the other being the cell which will create anti-bodies.
One type of anti-body will attach to the pathogen to attract phagocytes. The other type will disable the cell. A third type will group the pathogens together so that phagocytes can engulf them all.
If the memory cells every meet the pathogen again they will create the anti-bodies very quickly.

15 comments:

  1. spelling error in the pathogens section
    helpful blog!

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